31 Mar SHINING A LIGHT ON UNCOVERING THE PAST

In 1897, Mark Twain wrote “Truth is stranger than fiction, but it is because Fiction is obliged to stick to possibilities; Truth isn’t.” Now imagine a tale with as many historical twists and turns and exotic locations as a Dan Brown novel, but all of it fact, not fiction. You’d probably be interested in knowing more about such a story, wouldn’t you?

The protagonist in our tale of truth is a man named Archimedes, born in 287 BC in Syracuse on the island of Sicily. Archimedes was best known as a scientist and mathematician. He is credited with a description of what has become known as the Archimedes screw, which has been an effective way of moving water. He is also famously known for his ‘Eureka’ in the bathtub moment. Archimedes died in 212 BC. Through references of other ancient scholars, we know that Archimedes was considered brilliant, however his written works seemed to disappear from existence.

For nearly 7 centuries, Archimedes’ works appear sporadically as mentions or references in other works. Then, sometime around 530 AD, several of the works resurfaced and are seemingly consolidated by Isidore of Miletus, one of the two architects tasked with building Justinian I’s famous Hagia Sophia church in Constantinople. This consolidation began a path towards a wider audience for Archimedes. By the Middle Ages, Archimedes’ works, which had already been translated from Doric Greek into Greek, were now being translated into Syriac, Arabic, and Latin, as well as into Hebrew. However, it is Isidore of Miletus’ consolidated text which becomes our focal character.

The consolidated text is likely recopied sometime in the 9th century AD under the auspices of Leo the Geometer who was honored with his own school which became an intellectual center within Constantinople, one of the most cosmopolitan cities in the world at the time. Unfortunately, this flourishing period of learning ended abruptly in 1204 with the infamous Fourth Crusade. During the Fourth Crusade, crusaders ordered to protect the Christian holy lands sacked the then-Christian city of Constantinople. Following the sack, this manuscript disappears from the historical record and appears to have made its way to Jerusalem.

You may be wondering why someone might take a manuscript; certainly, paperback books today are very inexpensive things. But, in the Middle Ages, a manuscript represented a significant cost. For example, a 152-folio manuscript dated to roughly 1100 cost nearly $1660 in today’s currency to produce. Manuscripts were made to order and were hand copied on parchment or vellum. Parchment is a general term for animal skin (normally goat or sheep) which is specially prepared to be written on. Vellum, another type of parchment, is made from calf skin. The process of creating parchment is very labor intensive—the skin must be removed from the animal, stretched, cleaned, dried and prepared. One example of a two-volume set shows that the preparation of the parchment alone cost nearly $3045 in today’s currency! With such a high manufacturing cost, materials which could be recycled were. Parchment in particular could be recycled by washing with milk or oat bran or scraping the old text to remove it from the parchment. The only drawback of this method is that over time, the old text can faintly reappear. This is commonly known as a palimpsest, from the ancient Greek word which means scraped again.

Thus, our manuscript seems to have been taken to Jerusalem and “recycled” because the next time it shows up in the historical record is in 1844 when famed Biblical scholar Constantin von Tischendorf visited the Metochion of the Holy Sepulcher in Constantinople/Istanbul to examine manuscripts held in their library. He was apparently interested in having found what appeared to be an Eastern Orthodox prayer book with a mathematical text written underneath (a palimpsest). The find was significant enough that when he died, a folio from this manuscript was discovered among his papers, which he presumably “borrowed.” More time passes and in 1899, a Greek scholar, Athanasios Papadopoulos-Kerameus, catalogued the library and included the manuscript with a transcription of a few of the lines which he could make out.

This catalog caught the attention of one of the leading scholars of Archimedes. In 1906, the preeminent Archimedes scholar Johan Ludvig Heiberg came to Constantinople/Istanbul to see the manuscript himself because he had recognized the transcription to be of Archimedes works. Heiberg translated the palimpsest, photographed a number of the folios and published his findings in the following years, which included the news that the manuscript contained seven works of Archimedes. The manuscript proved, in fact, to be the sole source in Greek for two of Archimedes’ works!

Sometime after 1920, the manuscript disappeared again and, despite cropping up briefly in the late 1920’s, it remained an enigma. Then, in 1998, the manuscript again appeared as a French family offered it for sale through Christie’s . Despite a last minute legal bid by the Greek Orthodox Patriarchate of Jerusalem which tried to stop the sale, the manuscript was sold to an anonymous bidder. The manuscript was deposited by the owner at the Walters Art Museum in Baltimore, Maryland in 1999 for conservation, imaging and study.

This may sound like the end of our story, but in some ways, it is just the beginning. The Walters Art Museum team undertook a revolutionary imaging technique to reveal the obscured text. Using multispectral imaging, the team was able to reveal nearly 80 percent of the palimpsest. Multispectral imaging is the use of filters or other tools to separate various wavelengths of light during the imaging process to help reveal to human vision that which was previously thought invisible. Through further use of multispectral imaging, the Archimedes Palimpsest as it is known, continues to deliver new surprises, including the presence of three other ancient texts in addition to the Archimedes material.

Multispectral imaging is now used in many museums, libraries and archives to help discover the invisible. It’s not only a tool useful for manuscripts, but also for paintings which hide their own secrets in the form. It also allows for non-invasive forgery detection for both paintings and manuscripts.

Simulated images

If you find this post interesting and you want to know more about multispectral imaging and its application, please consider joining us at the Trust on April 6th at 9am for a talk by Dr. Antonino Cosentino of Cultural Heritage Science Open Source.

About Author: Kristin A. Phelps is the Director of Cultural Heritage Technology and Innovation at the Puerto Rico Science, Technology and Research Trust. She is a former archaeologist and experienced photographer and digitizer with training in conservation. Kristin has worked at the British Library, the British Museum and Petrie Museum, pursuing her research interests in Cultural Heritage Imaging. She is passionate about using visual digital content to open up museum and library collections to the public.